Liquid dispensing apparatus

ABSTRACT

A PETROL PUMP FOR DISPENSING PLURALITY OF PETROLS OF DIFFERENT OCTANE RATINGS HAVING AN INTERLOCK PREVENTING OPERATION OF THE MOTOR OF THE PUMP WHILST THE SELECTED BLEND IS BEING CHANGED.

Feb; 13, 1973 2 Shoets -Sheet 1 Filed Nov. 5, 1970 Feb. 13, 1973 c. R. PETYT 3,715,166

' I uqum msrsusme APPARATUS Filad Nov. 5, 1970 2 shoets sheet I United States Patent US. Cl. 222-- 3 Claims ABSTRACT OF THE DISCLOSURE A petrol pump for dispensing a plurality of petrols of different octane ratings having an interlock preventing operation of'the motor of the pump whilst the selected blend is being changed.

This invention relates to apparatus for dispensing liquids and is particularly concerned with apparatus for dispensing blends of a plurality of petrols having different octane ratings.

The blend to be dispensed by such apparatus is normally set by an operator turning a handle or knob on the casing of the pump and, due to the mechanism employed for computing the price of any selected blend, it is desirable for the blend not to be changed during any particular dispensing operation.

This desiration is achieved with apparatus for dispensing blends of a plurality of different liquids, in accordance with the invention, which apparatus comprises a pump for delivering the liquids, a motor for driving the pump, a switch device for activating and de-activating the motor, a manual switch lever for operating said switch device, means for determining the relative proportions of the selected blend, a blend selection device for activating the said means for determining the relative proportions of the selected blend, wherein the improvement comprises an interlock having part engaging a part of the blend selection device and a linkage connecting said part and the switch device, the arrangement being such that alteration of the selection device moves the said part causing the switch device to switch off the motor whilst the blend seletced is being changed.

The interlock linkage preferably includes a detent member engaging in a selected one of a number of grooves in the periphery of a disc connected to the blend selection device, the position of the disc and hence the grooves determining the blend to be dispensed, the detent member being connected by suitable linkage to the motor switch, the switch being opened when the detent member is moved from a groove onto the periphery of the disc i.e. when the blendis being changed, if the switch has not already been opened by the normal on/off control on the pump casing. When the detent member drops into a groove then the switch is enabled to be closed on operation of the normal main switch.

The movement of the interlock linkage may be employed also to render ineffective other parts of the pump, e.g. part of the price calculating equipment allowing this to be adjusted for the new blend without damage.

The invention will now be further described by way of example with reference to the accompanying drawings in which:

FIG. 1 is a diagrammatic, exploded, view showing a part of the blend selection device;

FIG. 2 is an isometric view of part of the interior of a pump in accordance with the invention showing the connection between the blend selection device and the interlock linkage.

3,716,166 Patented Feb. 13, 1973 When it is desired to change the blend of two petrols to be dispensed by the pump, the knob 2 which projects from the pump casing on the same side of the pump as the hose cock, is turned. This knob is pinned to a shaft 4 carrying a gear 6 meshing with a corresponding gear 8 on a freely rotating shaft 10. The shaft 10 carries at its other end a further gear wheel 12 meshing with a gear wheel 14 which is freely mounted on the shaft 4 and which carries on the outside of the casing, a pointer 16. The ratio between the gears 6 and 8 and between gears 12 and 14 is such that the knob 2 has to be turned through two rotations to move the indicator 16 from the two extreme blend proportions indicated at A and B on the indicating disc 18. The reduction gearing provides a reduction in the torque required to effect a change of blend.

The shaft 4 carries at its inner end a further gear 20 meshing with a corresponding gear 22 on a shaft 24 extends across the interior of the casing as indicated in FIG. 2 and carries at its other end a gear 26 which meshes with a corresponding gear 28 to drive a gear 30 which is mounted on a shaft (not shown) which shaft actuates a proportioning meter device generally at 32 which is described in detail in US. Pat. No. 3,486,662 and which acts so to control the proportions of the two petrols being dispensed as to achieve a blend corresponding to the setting which is predetermined by the angular position of the shaft 24 and which is indicated by the position of the pointer 16 on the display plate 18.

The shaft, carrying the gear 30, also carries a circular detent plate 32 the periphery of which is notched at 34, each notch corresponding to one of the blend settings A, B, or C indicated in FIG. 1. A detent roller 36 rests on the periphery of the detent disc and is biassed towards the centre of the disc by means of a spring (not shown).

Thus when the knob 2 has been turned to the correct angular position for one of the predetermined blend settings an operator can feel that that position has been achieved by reason of the roller 36 engaging in one of the notches 34.

In addition the roller 36 comprises a part of the interlock linkage and movement of the roller from its position as shown in FIG. 2 where it is engaged in one of the notches, to a position in which it rides on the periphcry of the disc which will occur whenever the blend is changed, thus causing a shaft 38 which is rotatably mounted on a shaft 40 and which is connected toone end of the roller bracket 42, to move angularly in a direction to depress the outer end of a lever 44 connected to the inner end of the shaft 38, this movement of the lever 44 acting to depress the end 46 of a lever 48 pivotted at its other end 50. This causes a rod 52 which is pivotally connected to the lever 48 at 54, to move downwardly to operate a differential lever mechanism (not shown) to cause a micro-switch (not shown) controlling the main pump units of the system to be switched off if it has not already been switched off by the normal on/off switch available to an operator on the outside of the casing and which is not shown in the drawings. The differential lever mechanism holds the micro-switch in this off position until the main on/off switch control is operated.

Thus the main pump units are switched off whenever the blend is changed and the operator cannot change the blend selection during a delivery and consequent errors both in the requested blend and computed price are avoided.

When the new blend is selected the roller 36 re-engages in a further one of the slots 34 causing a relative lifting of the rod 52 to cause the differential lever mechanism to be so positioned as to allow the micro-switch to be moved to the on position by the main on/off switch when it is desired to energise the main pump units to dispense the new blend.

The interlock linkage is also employed to disengage certain other parts of the pump mechanism which would otherwise either prevent a change of blend or be damaged by a change of blend. For example the pivot 50 which is connected to the link 48 is connected to a pair of arms 55 carrying push rods 56 and which, when the roller 36 is on the periphery of the disc 32 i.e. when the blend is being changed, cause the driving of the two contrate gears 58, which form part of the calculating mechanism of the pump and which are described in detail in the specification of US. Pat. 3,478,927 to be disengaged. When the new blend setting is selected, the contrate gear/drive wheel ratio is aligned by means of the pin wheel 60, at the same time that the detent disc 32 is rotated and as described in the specification of US. Pat. No. 3,420,409.

When the roller 36 drops into a further slot 34 the drive pinions re-engage the contrate gears. The proportioning meter device 32 includes two internal stops (not shown) which limit the rotation of the detent disc 32 to 324, the two extremites of this movement corresponding to the two extremes of blend selection as indicated at A and B in FIG. 1 and as determined by the position of the two adjustable shoulders 62 which determin the ends of the half slots 34 at these positions. When either of these two extreme blends is selected i.e. when it is desired to dispense only one or other of the two petrols a pressure regulating valve such as that described in the specification of published Great Britain patent specification No. 1,208,562 is automatically set to allow delivery of one grade of fuel only by the operation of a pin 64 which is secured to a gear 66 driven by the gear wheel 30 and which forms part of the blend selection device.

It will be appreciated that since the micro-switch remains in the off position so long as the push rod 52 is depressed i.e. so long as the roller remains on the periphery of the detent disc 32, the pump can only operate when a proper selection of one of the predetermined blends has been made i.e. when the roller 36 is properly engaged in one of the slots 34.

What I claim is:

1. Apparatus for dispensing blends of a plurality of liquids comprising: a pump for delivering the liquids; a motor for driving the pump; a switch device for activating and de-activating the motor; a manual switch lever for Operating said switch device; means for determining the relative proportions of the selected blend; a blend selection device for activating said means for determining the relative proportions of the selected blend; said switch device further including an interlock linkage means arranged for cooperation with the blend selection device, with the linkage including a rotary stop member arranged to advance into the path of a pivotal member connected to the switch device and located in the plane of rotation of said rotary stop member, the arrangement being such that alteration of the blend selection device actuates the linkage means causing the switch device to switch off the motor while the blend selected is being changed.

2. Apparatus as claimed in claim 1 wherein the interlock includes a disc having grooves formed in its periphery and connected to the blend selection device for rotation movement therewith; and a detent member biased to engage the periphery of the disc, the position of the disc and hence said grooves corresponding to the blend to be dispensed.

3. Apparatus as claimed in claim 2 wherein the detent member is connected to said switch device, rotation of the disc causing the detent member to move out of a groove onto the periphery of the disc thereby causing the switch device to open and the closure of the switch device being achieved by operation of manual switch lever when the detent member is engaged in a groove.

References Cited UNITED STATES PATENTS 2,594,181 4/1952 Kliegl et al 200 C 3,152,724 10/1964 Jauch ct al ZZZ-26 STANLEY H. TOLLBERG, Primary Examiner 

